Managing high-grade prostatic intraepithelial neoplasia (HGPIN) and atypical glands on prostate biopsy

Clinical and histopathological parameters in transrectal ultrasound-guided biopsies associated with tumor upgrading after radical prostatectomy: A comparative analysis of risk groups

BACKGROUND

Thanks to technological advances, prostate cancer (PCa) can be diagnosed at a younger age. It is known that most of these patients are in the low-intermediate risk group, and the histological grade of the tumor increases in half of those undergoing radical prostatectomy (Rp) compared to their diagnostic biopsies. This is especially important in terms of active surveillance (AS) and/or the timely evaluation of curative treatment options in patients diagnosed at an early age. Our aim was to investigate clinical and histopathological parameters that may be associated with an increase in the histological grade of the tumor in patients with acinar adenocarcinoma who were diagnosed by transrectal ultrasound-guided biopsy (TRUS-Bx) and underwent Rp.

METHODS

A total of 205 patients with classical acinar adenocarcinoma diagnosed by TRUS-Bx without metastasis and who underwent Rp were grouped according to the D'Amico risk classification. Age at diagnosis, serum prostate-specific antigen (PSA), PSA density, prostate volume, Prostate Imaging Reporting and Data System (PI-RADS) score, clinical stage, Gleason Grade Group (GGG), high-grade intraepithelial neoplasia in tumor-free cores (HGPIN) (single and ≥2 cores), perineural invasion (PNI), and lymphovascular invasion (LVI) was obtained. Additionally, GGG, pathological stage, lymph node metastasis, surgical margin positivity, and tumor volume obtained from Rp were evaluated. Comparisons were made between the case groups in which the tumor grade increased and remained the same, in terms of age, serum PSA, PSA density, HGPIN in tumor-free cores (single and ≥2 cores), PNI, and LVI in all biopsies (with or without tumors), as well as risk groups. In addition, the relationships of HGPIN in tumor-free cores (single and ≥2 cores), PNI, and LVI on TRUS-Bx with age, serum PSA and PSA density, tumor volume, surgical margin positivity, pathological stage, lymph node metastasis, and risk groups were examined separately.

RESULTS

Of the patients, 72 (35.1%) were in the low-risk group, 95 (46.3%) in the intermediate-risk group, and 38 (18.5%) in the high-risk group. Most of the patients with an increased histological grade (n = 38, 48.1%) were in the low-risk group (p < 0.05) and had an advanced median age. HGPIN in single and ≥2 tumor-free cores and PNI were more common in these patients (p < 0.01, p < 0.001, and p < 0.05, respectively). According to the multivariable analysis, advanced age (odds ratio [OR]: 1.087, 95% confidence interval [CI]: 1.029-1.148, p < 0.05), high serum PSA (OR: 1.047, 95% CI: 1.006-1.090, p < 0.05), HGPIN in ≥2 tumor-free cores (OR: 6.346, 95% CI: 3.136-12.912, p < 0.001), and PNI (OR: 3.138, 95% CI: 1.179-8.356, p < 0.05) were independent risk factors for a tumor upgrade. Furthermore, being in the low-risk group was an independent risk factor when compared to the intermediate- and high-risk groups (OR: 0.187, 95% CI: 0.080-0.437, p < 0.001 and OR: 0.054, 95% CI: 0.013-0.230, p < 0.001, respectively). The HGPIN diagnosis was more common in the low- and intermediate-risk groups. Advanced age at diagnosis, high serum PSA and PSA density values were associated with PNI on TRUS-Bx. High serum PSA and PSA density values were associated with LVI on TRUS-Bx. Surgical margin positivity was higher in cases with PNI and LVI detected by TRUS-Bx. HGPIN in ≥2 tumor-free cores, PNI, and LVI on TRUS-Bx were associated with a higher rate of lymph node metastases.

CONCLUSIONS

In patients diagnosed with acinar adenocarcinoma, the presence of HGPIN even in a single tumor-free core on TRUS-Bx was found to be significant in terms of showing an increase in the histological tumor grade in Rp. The diagnosis of HGPIN in ≥2 tumor-free cores on TRUS-Bx was determined as an independent risk factor for an increased Gleason score after Rp. Furthermore, an advanced age, a high serum PSA value, being in the low-risk group, and the presence of PNI were associated with a tumor upgrade. HGPIN in ≥2 tumor-free cores, PNI, and LVI were also associated with lymph node metastasis. Therefore, the diagnosis of HGPIN should be signed out on pathological reports.

Recent insights on the clinical, pathological, and molecular features of intraductal carcinoma of the prostate

Intraductal carcinoma of the prostate, a unique histopathologic entity that is often observed (especially in advanced prostate cancer), is characterized by the proliferation of malignant cells within normal acini or ducts surrounded by a basement membrane. Intraductal carcinoma of the prostate is almost invariably associated with an adjacent high-grade carcinoma and is occasionally observed as an isolated subtype. Intraductal carcinoma of the prostate has been demonstrated to be an independent poor prognostic factor for all stages of cancer, whether localized, de novo metastatic, or castration-resistant. It also has a characteristic genetic profile, including high genomic instability. Recognizing and differentiating it from other pathologies is therefore important in patient management, and morphological diagnostic criteria for intraductal carcinoma of the prostate have been established. This review summarizes and outlines the clinical and pathological features, differential diagnosis, molecular aspects, and management of intraductal carcinoma of the prostate, as described in previous studies. We also present a discussion and future perspectives regarding intraductal carcinoma of the prostate.

Regional Histopathology and Prostate MRI Positivity: A Secondary Analysis of the PROMIS Trial

Background The effects of regional histopathologic changes on prostate MRI scans have not been accurately quantified in men with an elevated prostate-specific antigen (PSA) level and no previous biopsy. Purpose To assess how Gleason grade, maximum cancer core length (MCCL), inflammation, prostatic intraepithelial neoplasia (PIN), or atypical small acinar proliferation within a Barzell zone affects the odds of MRI visibility. Materials and Methods In this secondary analysis of the Prostate MRI Imaging Study (PROMIS; May 2012 to November 2015), consecutive participants who underwent multiparametric MRI followed by a combined biopsy, including 5-mm transperineal mapping (TPM), were evaluated. TPM pathologic findings were reported at the whole-prostate level and for each of 20 Barzell zones per prostate. An expert panel blinded to the pathologic findings reviewed MRI scans and declared which Barzell areas spanned Likert score 3-5 lesions. The relationship of Gleason grade and MCCL to zonal MRI outcome (visible vs nonvisible) was assessed using generalized linear mixed-effects models with random intercepts for individual participants. Inflammation, PIN, and atypical small acinar proliferation were similarly assessed in men who had negative TPM results. Results Overall, 161 men (median age, 62 years [IQR, 11 years]) were evaluated and 3179 Barzell zones were assigned MRI status. Compared with benign areas, the odds of MRI visibility were higher when a zone contained cancer with a Gleason score of 3+4 (odds ratio [OR], 3.1; 95% CI: 1.9, 4.9; P < .001) or Gleason score greater than or equal to 4+3 (OR, 8.7; 95% CI: 4.5, 17.0; P < .001). MCCL also determined visibility (OR, 1.24 per millimeter increase; 95% CI: 1.15, 1.33; P < .001), but odds were lower with each prostate volume doubling (OR, 0.7; 95% CI: 0.5, 0.9). In men who were TPM-negative, the presence of PIN increased the odds of zonal visibility (OR, 3.7; 95% CI: 1.5, 9.1; P = .004). Conclusion An incremental relationship between cancer burden and prostate MRI visibility was observed. Prostatic intraepithelial neoplasia contributed to false-positive MRI findings. ClinicalTrials.gov registration no. NCT01292291 © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Harmath in this issue.

Identification of prostate cancer using multiparametric MR imaging characteristics of prostate tissues referenced to whole mount histopathology

In this study, the objective was to characterize the MR signatures of the various benign prostate tissues and to differentiate them from cancer. Data was from seventy prostate cancer patients who underwent multiparametric MRI (mpMRI) and subsequent prostatectomy. The scans included T2-weighted imaging (T2W), diffusion weighted imaging, dynamic contrast-enhanced MRI (DCE MRI), and MR spectroscopic imaging. Histopathology tissue information was translated to MRI images. The mpMRI parameters were characterized separately per zone and by tissue type. The tissues were ordered according to trends in tissue parameter means. The peripheral zone tissue order was cystic atrophy, high grade prostatic intraepithelial neoplasia (HGPIN), normal, atrophy, inflammation, and cancer. Decreasing values for tissue order were exhibited by ADC (1.8 10^-3 mm²/s to 1.2 10^-3 mm²/s) and T2W intensity (3447 to 2576). Increasing values occurred for DCE MRI peak (143% to 157%), DCE MRI slope (101%/min to 169%/min), fractional anisotropy (FA) (0.16 to 0.19), choline (7.2 to 12.2), and choline / citrate (0.3 to 0.9). The transition zone tissue order was cystic atrophy, mixed benign prostatic hyperplasia (BPH), normal, atrophy, inflammation, stroma, anterior fibromuscular stroma, and cancer. Decreasing values occurred for ADC (1.6 10^-3 mm²/s to 1.1 10^-3 mm²/s) and T2W intensity (2863 to 2001). Increasing values occurred for DCE MRI peak (143% to 150%), DCE MRI slope (101%/min to 137%/min), FA (0.18 to 0.25), choline (7.9 to 11.7), and choline / citrate (0.3 to 0.7). Logistic regression was used to create parameter model fits to differentiate cancer from benign prostate tissues. The fits achieved AUCs ≥0.91. This study quantified the mpMRI characteristics of benign prostate tissues and demonstrated the capability of mpMRI to discriminate among benign as well as cancer tissues, potentially aiding future discrimination of cancer from benign confounders.

The current recommendation for the management of isolated high-grade prostatic intraepithelial neoplasia

OBJECTIVE

To analyse the current predictive value of isolated high-grade prostatic intraepithelial neoplasia (HGPIN) for clinically significant prostate cancer (csPCa) detection in repeat biopsies.

PATIENTS AND METHODS

A cohort of 293 men with isolated HGPIN detected in previous biopsies performed without multiparametric magnetic resonance imaging (mpMRI), and who underwent repeat biopsy within 1 to 3 years, was analysed. Pre-repeat biopsy mpMRI and guided biopsies to suspicious lesions (Prostate Imaging - Reporting and Data System [PI-RADS] ≥3) and/or and systematic biopsies were performed. Persistent prostate cancer (PCa) suspicion, defined as sustained serum prostate-specific antigen level >4 ng/mL and/or abnormal digital rectal examination, was present in 248 men (84.6%), and was absent in 45 men (15.4%). A control group of 190 men who had no previous HGPIN, atypical small acinar proliferation or HGPIN with atypia who were scheduled to undergo repeat biopsy due to persistent PCa suspicion were also analysed. csPCa was defined as tumours of Grade Group ≥2.

RESULTS

In the subset of 45 men with isolated HGPIN, in whom PCa suspicion disappeared, only one csPCa (2.2%) and one insignificant PCa (iPCa) were detected. csPCa was detected in 34.7% of men with persistent PCa suspicion and previous HGPIN, and in 28.4% of those without previous HGPIN (P =0.180). iPCa was detected in 12.1% and 6.3%, respectively (P =0.039). Logistic regression analysis showed that the risk of csPCa detection was not predicted by previous HGPIN: odds ratio (OR) 1.369 (95% confidence interval [CI] 0.894-2.095; P =0.149); however, previous HGPIN increased the risk of iPCa detection: OR 2.043 (95% CI 1.016-4.109; P =0.006).

CONCLUSION

The risk of csPCa in men with isolated HGPIN, in whom PCa suspicion disappears, is extremely low. Moreover, in those men in whom PCa suspicion persists, the risk of csPCa is not influenced by the previous finding of HGPIN. However, previous HGPIN increases the risk of iPCa detection. Therefore, repeat prostate biopsy should not be recommended solely because of a previous HGPIN.

Current Understanding and Management of Intraductal Carcinoma of the Prostate

PURPOSE OF REVIEW

This review will discuss current understanding and management approaches of Intraductal carcinoma of the prostate (IDC-P). IDC-P is a histological finding characterized by neoplastic cells that expand but do not invade prostate ducts.

RECENT FINDINGS

The presence of IDC-P on a prostate biopsy is almost always associated with an invasive disease component and is independently associated with worse clinical outcomes in both early and late disease. These tumors are enriched for mutations in homologous DNA recombination repair (HRR) leading to high genomic instability. Multiparametric MRI with targeted biopsy may aid in diagnosis. Given the poor clinical outcomes associated with this histologic entity, its presence in biopsies should warrant consideration of aggressive management.

Prediction of clinically significant prostate cancer after negative prostate biopsy: The current value of microscopic findings

OBJECTIVE

To assess the current ability of atypical small acinar proliferation (ASAP), multifocal high-grade prostatic intraepithelial neoplasia (mHGPIN), HGPIN with atypia (PINATYP) and other non-malignant lesions to predict clinically significant prostate cancer (csPCa) in repeat prostate biopsies.

METHODS

This retrospective study analyzed 377 repeat prostate biopsies, carried out between 2.014 and 2.017, and excluding those with previous PCa or 5-alpha reductase inhibitors treatment. ASAP, mHGPIN, PINATYP, prostatic atrophy, prostatic hyperplastic atrophy, proliferative inflammatory atrophy (PIA), chronic prostatitis, acute prostatitis, or granulomatous prostatitis, were prospectively reported after 12-core transrectal ultrasound (TRUS) systematic negative previous biopsies. 3T-multiparametric magnetic resonance imaging (mpMRI) was performed previous repeat biopsies. At least 2-core TRUS targeted biopsies of Prostate Imaging-Reporting and Data Systemv2 lesions ≥3, and/or 12-core TRUS systematic biopsy were performed in repeat prostate biopsies. The main outcome measurements were csPCa detection, which was defined when the International Society of Uro-Pathology group grade >1 and avoided biopsies. After logistic regression analysis the most efficient model was selected, nomogram was designed with internal validation, and clinical utility was analyzed.

RESULTS

Normal benign tissue alone was present in less than 2% of previous negative biopsies. mHGPIN (39.7%), ASAP (4.3%) and PINATYP (3.7%) failed to predict csPCa risk in repeat biopsies. The finding of PIA (38.2%) associated with a decreased the risk of csPCa with an Odd ratio of 0.54 (95% confidence interval: 0.31-0.95), P= 0.031. The area under the curve, to predict csPCa, of mpMRI was 0.736, increasing up to 0.860 (95% confidence internal:0.82-0.90) when PSA density, age, digital rectal examination, and differential PSA between biopsies and PIA finding were integrated in a predictive model. At 6% threshold, more than 20% of repeat prostate biopsies were saved without missing csPCa.

CONCLUSION

Currently, mHGPIN in negative prostate biopsy seems not able to predict the risk of future csPCa. The low incidence of ASAP and PINATYP, in our series, did not allow us to draw conclusions. PIA finding associated with a reduced risk of csPCa, and it could be integrated in a useful based-mpMRI predictive nomogram.

Validating fPSA Glycoprofile as a Prostate Cancer Biomarker to Avoid Unnecessary Biopsies and Re-Biopsies

BACKGROUND

To compare the clinical performance of a new PCa serum biomarker based on fPSA glycoprofiling to fPSA% and PHI.

METHODS

Serum samples from men who underwent prostate biopsy due to increased PSA were used. A comparison between two equal groups (with histologically confirmed PCa or benign, non-cancer condition) was used for the clinical validation of a new glycan-based PCa oncomarker. SPSS and R software packages were used for the multiparametric analyses of the receiver operating curve (ROC) and for genetic algorithm metaheuristics.

RESULTS

When comparing the non-cancer and PCa cohorts, the combination of four fPSA glycoforms with two clinical parameters (PGI, prostate glycan index (PGI)) showed an area under receiver operating curve (AUC) value of 0.821 (95% CI 0.754-0.890). AUC values were 0.517 for PSA, 0.683 for fPSA%, and 0.737 for PHI. A glycan analysis was also applied to discriminate low-grade tumors (GS = 6) from significant tumors (GS ≥ 7).

CONCLUSIONS

Compared to PSA on its own, or fPSA% and the PHI, PGI showed improved discrimination between presence and absence of PCa and in predicting clinically significant PCa. In addition, the use of PGI would help practitioners avoid 63.5% of unnecessary biopsies, while the use of fPSA% and PHI would help avoid 17.5% and 33.3% of biopsies, respectively, while missing four significant tumors (9.5%).

Large-Gland Proliferations of the Prostate

Large-gland proliferations of the prostate have gained considerable attention in the past decade. The differential diagnosis is quite broad but can be refined using histologic criteria and, sometimes, immunostains. Pathologists have come to realize that cribriform and intraductal as well as ductal carcinomas are particularly aggressive patterns, and should name them in diagnostic reporting when present.

Is Ki67 prognostic for aggressive prostate cancer? A multicenter real-world study

AIM

To test if Ki67 expression is prognostic for biochemical recurrence (BCR) after radical prostatectomy (RP).

METHODS

Ki67 immunohistochemistry was performed on tissue microarrays constructed from specimens obtained from 464 men undergoing RP at the Durham and West LA Veterans Affairs Hospitals. Hazard ratios (HR) for Ki67 expression and time to BCR were estimated using Cox regression.

RESULTS

Ki67 was associated with more recent surgery year (p < 0.001), positive margins (p = 0.001) and extracapsular extension (p < 0.001). In center-stratified analyses, the adjusted HR for Ki67 expression and BCR approached statistical significance for west LA (HR: 1.54; p = 0.06), but not Durham (HR: 1.10; p = 0.74).

CONCLUSION

This multi-institutional 'real-world' study provides limited evidence for the prognostic role of Ki67 in predicting outcome after RP.

Clinical implications of PTEN loss in prostate cancer

Genomic aberrations of the PTEN tumour suppressor gene are among the most common in prostate cancer. Inactivation of PTEN by deletion or mutation is identified in ∼20% of primary prostate tumour samples at radical prostatectomy and in as many as 50% of castration-resistant tumours. Loss of phosphatase and tensin homologue (PTEN) function leads to activation of the PI3K-AKT (phosphoinositide 3-kinase-RAC-alpha serine/threonine-protein kinase) pathway and is strongly associated with adverse oncological outcomes, making PTEN a potentially useful genomic marker to distinguish indolent from aggressive disease in patients with clinically localized tumours. At the other end of the disease spectrum, therapeutic compounds targeting nodes in the PI3K-AKT-mTOR (mechanistic target of rapamycin) signalling pathway are being tested in clinical trials for patients with metastatic castration-resistant prostate cancer. Knowledge of PTEN status might be helpful to identify patients who are more likely to benefit from these therapies. To enable the use of PTEN status as a prognostic and predictive biomarker, analytically validated assays have been developed for reliable and reproducible detection of PTEN loss in tumour tissue and in blood liquid biopsies. The use of clinical-grade assays in tumour tissue has shown a robust correlation between loss of PTEN and its protein as well as a strong association between PTEN loss and adverse pathological features and oncological outcomes. In advanced disease, assessing PTEN status in liquid biopsies shows promise in predicting response to targeted therapy. Finally, studies have shown that PTEN might have additional functions that are independent of the PI3K-AKT pathway, including those affecting tumour growth through modulation of the immune response and tumour microenvironment.